Hognose Alpha1

This is an alpha release of the PiTubeDirect Hognose version.

There are two main new features in Hognose:

1. A JIT-based implementation of the 65C02 Co Processor that is upto 4x faster:

• Pi 0: Speedup is 1.45x
  • Co Pro 0: 282.60MHz
  • Co Pro 24: 409.09MHz
• Pi 3A+: Speedup is 3.16x
  • Co Pro 0: 339.10MHz
  • Co Pro 24: 1072.33MHz
• Pi 4:: Speedup is 4.30x
  • Co Pro 0: 366.79MHz
  • Co Pro 24: 1576.67MHz

(measured using the BASIC 2 version of CLOCKSP)

The JIT 6502 (Co Pro 24) is now the default Co Processor; this can be changed by editing cmdline.txt.

Thanks for Dominic (dp11) for creating the new JIT 6502 Co Pro!

2. A BBC compatible VDU driver that allows use of the Pi's HDMI port as a secondary display:
   

See this Wiki page for more details : Pi VDU Driver

Here is a more complete log of the changes since the Gecko release:

• 6502 JIT (Co Pro 24)
• VDU Driver for Pi's HDMI port
• Fixed debugger ioread bug (Coverity)
• FIxed Pi 4 overclocking bug
• Native ARM Co Pro: OSBYTE SWI returns unexpected value in R1 (#120)
• 32016: fix a disassembly issue with EaPlusRn index register
• 32016: fix a disassembly issue with EaPlusRn scaled indexed addressing
• 32016: Prevent disassembly os junk causing traps
• 32016: Implement TOS for access class regaddr (fixes #118)
• Fast6502: Optional fix for JSR/RTS stack wrap issue with TwinHead
• 65816: Fix flag bug in 16-bit ROL (found with Drass tests)